Combinations of a 4-pyrimidinesulfamide derivative with active ingredients for the treatment of endothelin related diseases

ABSTRACT

The present invention concerns the compound aprocitentan, {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide, and its use as endothelin receptor antagonist, in combination with other active ingredients or therapeutic agents including an angiotenin receptor blocker, and/or a calcium channel blocker, and preferably a diuretic which is a thiazide-like diuretic, in the prophylaxis or treatment of certain endothelin related diseases. The invention further relates to pharmaceutical compositions comprising aprocitentan in combination with said other active ingredients or therapeutic agents. The invention further relates to such pharmaceutical compositions comprising novel crystalline forms of aprocitentan.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No. 16/489,227, filed on Aug. 27, 2019, now issued as U.S. Pat. No. 11,174,247, which claims benefit under 35 U.S.C. 371 to PCT Application No. PCT/EP2017/078371, filed on Nov. 6, 2017, which claims the benefit of PCT Application Nos. PCT/EP2017/054489, filed on Feb. 27, 2017, and PCT/EP2017/061487, filed on May 12, 2017, the contents of each of which are incorporated herein by reference.

The present invention concerns the compound aprocitentan and its use as endothelin receptor antagonist, in combination with other active ingredients or therapeutic agents including an angiotenin receptor blocker (especially valsartan), and/or a calcium channel blocker (especially amlodipine), and preferably a diuretic which is a thiazide-like diuretic (especially hydrochlorothiazide or chlorthalidone), in the prophylaxis or treatment of certain endothelin related diseases. The invention further relates to pharmaceutical compositions comprising aprocitentan in combination with said other active ingredients or therapeutic agents. The invention further relates to such pharmaceutical compositions comprising novel crystalline forms of aprocitentan; pharmaceutical compositions prepared from such crystalline forms, and to the use of such crystalline forms in combination with said other active ingredients or therapeutic agents in the prophylaxis or treatment of said endothelin related diseases.

Aprocitentan, {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide (hereinafter also referred to as “COMPOUND”), has the formula I

The compound of formula I, also known under the name, and referred to as ACT-132577, is an endothelin receptor inhibitor and useful as endothelin receptor antagonist. The compound of formula I is a member of a structural family that was previously generically disclosed in WO 02/053557. In particular, the compound of formula I, while showing endothelin receptor antagonist activity, exhibits in vivo a much longer half-life and a much shorter clearance in comparison to corresponding alkylated derivatives. This makes the compound of formula I particularly suitable for long-acting pharmaceutical compositions, as disclosed in WO 2009/024906.

Because of its ability to inhibit the endothelin binding, the compound of formula I can be used for treatment of endothelin related diseases which are associated with an increase in vasoconstriction, proliferation or inflammation due to endothelin. Examples of such diseases are hypertension, pulmonary hypertension, coronary diseases, cardiac insufficiency, renal and myocardial ischemia, renal failure, cerebral ischemia, dementia, migraine, subarachnoidal hemorrhage, Raynaud's syndrome, digital ulcers and portal hypertension. They can also be used in the treatment or prevention of atherosclerosis, restenosis after balloon or stent angioplasty, inflammation, stomach and duodenal ulcer, cancer, melanoma, prostate cancer, prostatic hypertrophy, erectile dysfunction, hearing loss, amaurosis, chronic bronchitis, asthma, pulmonary fibrosis, gram negative septicemia, shock, sickle cell anemia, glomerulonephritis, renal colic, glaucoma, connective tissue diseases, therapy and prophylaxis of diabetic complications, complications of vascular or cardiac surgery or after organ transplantation, complications of cyclosporin treatment, pain, hyperlipidemia as well as other diseases, presently known to be related to endothelin. Particular examples of endothelin related diseases are hypertension related diseases comprising hypertension including especially difficult to treat/resistant hypertension; pulmonary hypertension; heart failure including especially chronic heart failure; reducing the risk of developing a major cardiovascular event (such as heart failure, myocardial infarction, stroke, or death from cardiovascular causes) in patients who are at cardiovascular risk (such as patients who have coronary artery disease and/or patients who have demonstrated clinical signs of congestive heart failure); angina pectoris; and diastolic dysfunction; erectile dysfunction; CKD (especially CKD of stages 1 to 4 as defined by the Kidney Disease Improving Global Outcomes (KDIGO) Guidelines (and notably CKD of stage 3), and in particular CKD of these stages caused by/associated with essential hypertension, especially resistant hypertension); and diabetes, and diabetes related diseases such as diabetic arteriopathy, diabetic nephropathy, diabetic retinopathy, diabetic vasculopathy; and reducing the risk of developing a major cardiovascular event (such as heart failure, myocardial infarction, stroke, or death from cardiovascular causes) in patients who have diabetes that is accompanied by at least one other cardiovascular risk factor (such as hypertension, especially resistant hypertension).

According to the 2014 American Society of Hypertension and International Society of Hypertension joint statement [Weber et al., “Clinical Practice Guidelines for the Management of Hypertension in the Community. A Statement by the American Society of Hypertension and the International Society of Hypertension.” J Clin Hypertens (2014), 16(1), 14-26], the 2013 European Society of Hypertension and European Society of Cardiology joint guideline [Mancia et al, J. Hypertens. (2013), 31, 1281-1357], as well as several national guidelines [Denolle et al., J Hum Hypertens. (2016), 30(11), 657-663; McCormack et al., Br J Cardiol (2013), 20 (suppl 1), S1-S16], resistant hypertension (rHT) (or difficult to treat hypertension) is defined as uncontrolled blood pressure (BP) (i.e., failure to lower BP to a pre-defined threshold) despite concurrent administration of three antihypertensive therapies of different pharmacological classes at maximal or optimal doses, including a diuretic. Thus, resistant hypertension patients include patients whose blood pressure is controlled with use of more than three medications. That is, patients whose blood pressure is controlled but require four or more medications to do so should be considered resistant to treatment (see e.g. Mancia et al, J. Hypertens. (2013)).

Clinical studies have shown that endothelin receptor antagonists (ERAs) may have significant treatment effect in patients suffering from hypertension and/or renal disease. However, therapeutic benefit needs to be weighted against potential side effects, such as the potential risk of teratogenic activity. In addition, both, selective ET_(A)-antagonists and dual antagonists of both the ET_(A) and ET_(B) receptor, may cause fluid retention, a common side effect associated with many previously studied ERAs. Whereas the risk-benefit balance is in most cases in favor of treatment with an ERA for indications such as pulmonary hypertension (as reflected in the past by successive market approvals e.g. for the ERAs the dual antagonists bosentan and macitentan, the ET_(A)-selective antagonist ambrisentan), ERAs have no role in the management of primary hypertension (Laffin et al. Seminars in Nephrology 2015, 35, 168-175), and side effects such as fluid retention may remain an issue when a potential treatment of rHT, chronic kidney disease or other hypertension related diseases with an ERA is considered.

The ET_(A)-selective endothelin receptor antagonist darusentan has been in development for the treatment of rHT (Bakris et al., Hypertension 2010, 56, 824-830, see also WO2007/098390). In a 14 week phase 3 trial in patients with rHT, it demonstrated efficacy on the reduction of ambulatory blood pressure, but failed to show significant treatment effect on the primary endpoint systolic blood pressure. Patients were eligible to participate if they had treatment resistant hypertension (systolic blood pressure of higher than 140 mm Hg) despite treatment with three or more antihypertensive drugs from different drug classes, including a diuretic, at optimized doses. A minimum dose of 25 mg per day of hydrochlorothiazide (or its equivalent for other thiazide diuretic drugs) was required. Even though during the trial diuretic therapy could be intensified at the discretion of the investigators to manage fluid retention, the most frequent adverse event associated with darusentan was fluid retention/edema at 28% versus 12% in each of the other groups. More patients withdrew because of adverse events on darusentan as compared with placebo.

WO2016/073846 provides a comprehensive summary of ERAs tested for various indications including CKD and rHT. Similarly to the observations made for darusentan mentioned above, also the ET_(A)-selective ERA avosentan, in a trial that investigated the use of avosentan to reduce proteinuria in patients with diabetes, showed significant treatment effect, associated with a significantly increased discontinuation of trial medications due to adverse events, predominantly related to fluid overload and congestive heart failure. The trial was terminated prematurely, and the authors conclude that “it may be that at dosages of 25 to 50 mg, avosentan is less selective for the ETA receptor and thus caused sodium and water retention and peripheral vasodilation with a potential fluid shift from the intravascular to extravascular space. The assumption of ETB receptor blockade with higher dosages of avosentan is further supported by data that showed a natriuretic effect of selective ETA receptor blockade in people who were treated with ACEIs (Mann et al., J Am Soc Nephrol. 2010, 21(3): 527-535.” WO2016/073846 provides further examples where fluid retention may have led to increased side effects for the ERAs bosentan, tezosentan, ambrisentan, and atrasentan. WO2016/073846 concludes in proposing a method of treating CKD with an ERA, especially with the ET_(A)-selective ERA atrasentan, using predictors of fluid retention; said method comprising the determination of a risk of fluid retention if an ERA were administered to the subject; and administering the ERA to the subject if the risk is at an acceptable level.

Preclinical and clinical data suggest that the ET_(A)-selective antagonists sitaxentan and ambrisentan pose a greater risk of fluid retention than the dual ERAs bosentan and macitentan (Vercauteren et al., JPET 2017, 361, 322-333). On the other hand, pre-clinical data showed that the synergistic effect on blood pressure of an ET_(A)-selective ERA in combination with the ACE inhibitor enalapril was abolished by simultaneous blockade of the ET_(B)-receptor (Goddard et al., J. Am. Soc. Nephrol. 2004, 15, 2601-2610).

It has been shown in a phase 2 trial that aprocitentan, an ERA resulting in effective dual blockade of the endothelin receptors, may result in efficacious control of blood pressure in subjects having essential hypertension, i.e. without background therapy (Actelion Pharmaceuticals Ltd, press release May 22, 2017). The overall frequency of adverse events was similar to those observed in the placebo group. Thus, different from the methods of WO2016/073846 no risk assessment and/or dose reduction to mitigate side effects related to fluid retention may be required for aprocitentan when used in the treatment of hypertension related diseases, especially resistant hypertension.

Moreover, it has been found in rat models of hypertension that aprocitentan may have synergistic pharmacological effect in combination with valsartan, and synergistic pharmacological effect in combination with amlodipine, compared to the effect of the respective active ingredients alone. In particular, when combined with three antihypertensive therapies of different pharmacological classes including valsartan, amlodipine, and a diuretic of the thiazide class such as commercially available Exforge HCT® (i.e. a fixed dose combination of valsartan/amlodipine/hydrochlorothiazide), aprocitentan may result in superior effect than spironolactone which is a standard available add-on treatment. Moreover, aprocitentan may have a different pharmacological profile than the predominantly ET_(A)-selective antagonists so far tested in resistant hypertension and other endothelin-related diseases. Thus, aprocitentan, an ERA resulting in effective dual blockade of the endothelin receptors, may be particularly suited for the treatment of resistant hypertension when prescribed in combination with one or more antihypertensive therapies of different pharmacological classes, including especially an angiotensin receptor blocker such as especially valsartan, a calcium channel blocker such as especially amlodipine, and a diuretic, especially a diuretic of the thiazide class (a thiazide-like diuretic) such as especially chlorothiazide, chlorthalidone, hydrochlorothiazide, indapamide, or metolazone. Such combination treatment may result in superior control of blood pressure compared to the treatment with such antihypertensive therapies alone, while maintaining a benign side effect profile even at optimal efficacious dosages of aprocitentan, not requiring e.g. the risk assessment methods of WO2016/073846 and/or dose reductions to mitigate side effects, e.g. related to fluid retention.

It has further been found that certain crystalline forms of aprocitentan that are suitable for the production of pharmaceutical compositions may under certain conditions be found. Said crystalline forms of COMPOUND are novel and may have advantageous properties in view of the potential use of COMPOUND as active pharmaceutical ingredient. Such advantages may include better flow properties; less hygroscopicity; better reproducibiliy in manufacturing (for example better filtration parameters, better reproducibility of formation, and/or better sedimentation); and/or defined morphology. Such crystalline forms of COMPOUND may be particularly suitable in a process of manufacturing certain pharmaceutical compositions. It has also been found that COMPOUND or a pharmaceutically acceptable salt thereof is particularly useful to treat certain disorders, in particular when used in combination with other active ingredients or therepeutic agents.

DESCRIPTION OF THE FIGURES

FIG. 1 shows the X-ray powder diffraction diagram of COMPOUND in a crystalline form A as obtained from Example 1. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 9.8° (18%), 9.9° (18%), 11.7° (14%), 14.5° (10%), 15.4° (14%), 15.6° (29%), 16.9° (19%), 17.2° (16%), 17.8° (100%), 18.6° (50%), 19.9° (54%), 20.0° (67%), 21.5° (24%), 21.9° (10%), 22.8° (18%), 23.2° (49%), 23.5° (83%), 24.9° (32%), 25.1° (20%), 25.3° (24%), 25.6° (33%), 25.9° (16%), 27.1° (23%), 27.3° (39%), 28.5° (13%), 29.0° (23%), 29.4° (15%), 30.1° (12%) and 30.6° (10%).

FIG. 2 shows the X-ray powder diffraction diagram of a dichloromethane solvate of the COMPOUND in a crystalline form B as obtained from Example 2. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 11.2° (16%), 16.2° (57%), 18.0° (21%), 18.6° (71%), 18.8° (36%), 19.8° (19%), 20.3° (100%), 22.4° (45%), 22.9° (28%), 24.3° (44%), 24.8° (11%), 25.0° (41%), 25.7° (22%), 26.1° (31%), 27.4° (20%), 29.4° (16%), 29.8° (38%) and 32.4° (12%).

FIG. 3 shows the X-ray powder diffraction diagram of COMPOUND in a crystalline form C as obtained from Example 3. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 7.8° (23%), 9.7° (42%), 15.7° (37%), 17.2° (16%), 17.8° (15%), 18.8° (26%), 19.8° (71%), 20.1° (51%), 20.6° (15%), 21.6° (15%), 22.0° (100%), 23.4° (27%), 23.6° (40%), 24.1° (23%), 24.5° (16%), 25.1° (13%), 25.3° (39%), 25.7° (28%), 26.8° (19%), 27.1° (16%), 28.5° (31%), 30.8° (13%) and 30.8° (13%).

FIG. 4 shows the X-ray powder diffraction diagram of COMPOUND in a crystalline form D as obtained from Example 4. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 4.6° (27%), 8.4° (15%), 8.6° (11%), 16.4° (17%), 16.8° (26%), 17.2° (10%), 18.6° (11%), 18.9° (18%), 19.3° (40%), 19.6° (45%), 20.1° (100%), 20.6° (55%), 20.8° (26%), 22.0° (10%), 22.7° (14%), 23.0° (24%), 23.5° (32%), 23.8° (12%), 24.2° (17%), 24.7° (20%), 25.1° (55%), 25.4° (22%), 25.6° (14%), 26.2° (16%), 26.8° (17%), 27.2° (28%), 28.1° (21%) and 28.1° (19%).

FIG. 5 shows the X-ray powder diffraction diagram of an acetonitrile solvate of the COMPOUND in a crystalline form E as obtained from Example 5. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 9.0° (21%), 9.5° (56%), 11.3° (61%), 14.5° (41%), 14.8° (15%), 15.6° (47%), 16.0° (26%), 16.5° (100%), 18.2° (84%), 18.7° (73%), 18.9° (56%), 20.2° (20%), 20.7° (56%), 22.8° (96%), 23.9° (22%), 24.5° (70%), 25.3° (77%), 25.6° (29%), 26.0° (14%), 26.6° (66%), 27.5° (27%), 29.6° (31%), 30.2° (66%) and 33.0° (13%).

FIG. 6 shows the X-ray powder diffraction diagram of COMPOUND in a crystalline form J as obtained from Example 6. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 4.0° (44%), 4.7° (14%), 6.5° (23%), 9.0° (27%), 16.1° (40%), 17.2° (11%), 18.7° (22%), 19.0° (58%), 19.4° (28%), 19.8° (46%), 20.7° (57%), 21.2° (17%), 21.9° (100%), 22.6° (14%), 23.2° (23%), 24.1° (37%), 24.8° (40%), 25.6° (42%), 27.0° (29%), 28.2° (27%), 29.0° (20%), 30.3° and 30.8° (10%).

FIG. 7 shows the X-ray powder diffraction diagram of a dimethylsulfoxide solvate of the COMPOUND in a crystalline form K as obtained from Example 7. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 10.9° (16%), 16.9° (18%), 18.2° (26%), 18.4° (30%), 18.6° (29%), 18.7° (55%), 19.3° (100%), 20.8° (35%), 21.2° (47%), 21.9° (26%), 24.3° (21%), 24.8° (24%), 25.4° (29%), 25.8° (22%), 26.7° (34%), 27.7° (13%), 27.8° (14%), 28.6° (15%), 29.4° (18%), 31.5° (23%) and 31.8° (12%).

FIG. 8 shows the X-ray powder diffraction diagram of an ethanol solvate of the COMPOUND in a crystalline form L as obtained from Example 8. The X-ray diffraction diagram shows peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parenthesis) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported): 9.1° (31%), 9.3° (34%), 11.3° (49%), 12.2° (10%), 14.6° (17%), 14.8° (46%), 15.7° (16%), 16.1° (10%), 16.4° (80%), 17.9° (17%), 18.2° (19%), 18.7° (96%), 20.0° (38%), 20.3° (100%), 22.6° (11%), 22.8° (76%), 23.2° (50%), 24.1° (14%), 24.5° (56%), 24.7° (68%), 25.4° (46%), 25.9° (32%), 26.4° (14%), 26.8° (22%), 27.7° (38%), 28.2° (12%), 29.7° (11%), 29.5° (64%), 29.8° (14%), 30.3° (14%), 30.5° (13%) and 32.4° (16%).

It is understood, that the crystalline forms disclosed herein comprise the COMPOUND in a crystalline form of the free base (i.e. not in form of a salt). Furthermore, said crystalline forms may comprise non-coordinated and/or coordinated solvent. Coordinated solvent is used herein as term for a crystalline solvate. Likewise, non-coordinated solvent is used herein as term for physiosorbed or physically entrapped solvent (definitions according to Polymorphism in the Pharmaceutical Industry (Ed. R. Hilfiker, VCH, 2006), Chapter 8: U. J. Griesser: The Importance of Solvates). Crystalline forms A and C are anhydrate or ansolvate forms, crystalline form B is a DCM solvate, crystalline form E is a MeCN solvate and crystalline form K is a DMSO solvate.

FIG. 9 shows the acute effects of ACT-132577 on mean arterial blood pressure (“MAP”) in conscious, male hypertensive Dahl salt sensitive rats.

FIG. 10 shows the acute effects of ACT-132577 on MAP in conscious, male hypertensive deoxycorticosterone acetate salt rats.

FIG. 11 shows the acute effects of ACT-132577 on MAP in conscious, male spontaneaously hypertensive rats.

FIG. 12 shows the acute effects of ACT-132577, used alone or in combination with valsartan, on MAP in conscious, male spontaneaously hypertensive rats.

FIG. 13 shows the acute effects of ACT-132577, used alone or in combination with valsartan, on MAP in conscious, male hypertensive deoxycorticosterone acetate salt rats.

FIG. 14 shows the acute effects of ACT-132577, used alone or in combination with enalapril, on MAP in conscious, male spontaneaously hypertensive rats.

FIG. 15 shows the acute effects of ACT-132577, used alone or in combination with amlodipine, on MAP in conscious, male hypertensive deoxycorticosterone acetate salt rats.

FIG. 16 shows the effects of chronic oral administration of ACT-132577 on MAP in conscious, male hypertensive deoxycorticosterone acetate salt rats.

FIG. 17 shows the effects of chronic oral administration of ACT-132577 on renal vascular resistance in conscious, male hypertensive deoxycorticosterone acetate salt rats.

FIG. 18 shows the acute dose-response effect of aprocitentan 1 mg/kg, 3 mg/kg, 10 mg/kg, 30 mg/kg) on haematocrit (Hct) 24 hours after a single oral administration to Wistar rats.

FIG. 19 shows acute effects of EXFORGE HCT® alone, and EXFORGE HCT® in combination with ACT-132577, in male spontaneaously hypertensive rats.

FIG. 20 shows acute effects of EXFORGE HCT® alone, and EXFORGE HCT® in combination with spironolactone, in male spontaneaously hypertensive rats.

FIG. 21 shows acute effects of EXFORGE HCT® alone, and EXFORGE HCT® in combination with ACT-132577, in male hypertensive deoxycorticosterone acetate salt rats.

FIG. 22 shows acute effects of EXFORGE HCT® alone, and EXFORGE HCT® in combination with spironolactone, in male hypertensive deoxycorticosterone acetate salt rats.

DETAILED DESCRIPTION OF THE INVENTION

1) A first embodiment relates to a pharmaceutical composition containing, as active principles, aprocitentan, or a pharmaceutically acceptable salt thereof, in combination with an angiotenin receptor blocker which is especially valsartan, or a pharmaceutically acceptable salt thereof, as well as at least one pharmaceutically acceptable excipient.

2) A second aspect of the present invention relates to a pharmaceutical composition containing, as active principles, aprocitentan, or a pharmaceutically acceptable salt thereof, in combination with

-   -   an angiotenin receptor blocker which is especially valsartan, or         a pharmaceutically acceptable salt thereof, and/or     -   a calcium channel blocker which is especially amlodipine, or a         pharmaceutically acceptable salt thereof;         as well as at least one pharmaceutically acceptable excipient.

3) A third aspect of the present invention relates to a pharmaceutical composition containing, as active principles, aprocitentan, or a pharmaceutically acceptable salt thereof, in combination with

-   -   an angiotenin receptor blocker which is especially valsartan, or         a pharmaceutically acceptable salt thereof;     -   a calcium channel blocker which is especially amlodipine, or a         pharmaceutically acceptable salt thereof; and     -   a diuretic which is a thiazide-like diuretic (notably         hydrochlorothiazide or chlorthalidone, especially         hydrochlorothiazide), or a pharmaceutically acceptable salt         thereof;         as well as at least one pharmaceutically acceptable excipient.

4) A further embodiment relates to a pharmaceutical composition according to embodiment 3), wherein the angiotenin receptor blocker is valsartan or a pharmaceutically acceptable salt thereof; the calcium channel blocker is amlodipine, or a pharmaceutically acceptable salt thereof; and the diuretic is hydrochlorothiazide or a pharmaceutically acceptable salt thereof, or chlorthalidone or a pharmaceutically acceptable salt thereof.

5) A further embodiment relates to a pharmaceutical composition according to embodiment 3) wherein said pharmaceutical composition comprises aprocitentan or a pharmaceutically acceptable salt thereof, in combination with valsartan or a pharmaceutically acceptable salt thereof, and amlodipine, or a pharmaceutically acceptable salt thereof; and in combination with hydrochlorothiazide or a pharmaceutically acceptable salt thereof, or chlorthalidone or a pharmaceutically acceptable salt thereof; wherein

-   -   aprocitentan or a pharmaceutically acceptable salt thereof is         comprised in a pharmaceutical unit dosage form suitable for the         oral administration of 2.5 to 100 mg (in particular 5 or 10 to         50 mg, notably 12.5 mg, 25 mg or 50 mg, especially 12.5 mg or 25         mg) per day of aprocitentan;     -   valsartan or a pharmaceutically acceptable salt thereof is         comprised in a pharmaceutical unit dosage form suitable for the         oral administration of 100 to 320 mg (in particular 160 or 320         mg, notably 160 mg) per day of valsartan;     -   amlodipine or a pharmaceutically acceptable salt thereof is         comprised in a pharmaceutical unit dosage form suitable for the         oral administration of 2 to 10 mg (in particular 5 or 10 mg,         notably 5 mg) per day of amlodipine; and     -   hydrochlorothiazide or a pharmaceutically acceptable salt         thereof, if present, is comprised in a pharmaceutical unit         dosage form suitable for the oral administration of 5 to 25 mg         (in particular 12.5 or 25 mg) per day of hydrochlorothiazide;         and chlorthalidone or a pharmaceutically acceptable salt         thereof, if present, is comprised in a pharmaceutical unit         dosage form suitable for the oral administration of 10 to 150 mg         (in particular 15 mg or 30 mg) per day of chlorthalidone.

6) A further embodiment relates to a pharmaceutical composition according to embodiment 4) wherein the diuretic is hydrochlorothiazide.

7) A further embodiment relates to a pharmaceutical composition according to embodiment 6) wherein

-   -   aprocitentan or a pharmaceutically acceptable salt thereof is         comprised in a pharmaceutical unit dosage form suitable for the         oral administration of 2.5 to 100 mg (in particular 5 or 10 to         50 mg, notably 12.5 mg, 25 mg or 50 mg, especially 12.5 mg or 25         mg) per day of aprocitentan;     -   valsartan or a pharmaceutically acceptable salt thereof is         comprised in a pharmaceutical unit dosage form suitable for the         oral administration of 100 to 320 mg (in particular 160 or 320         mg, notably 160 mg) per day of valsartan;     -   amlodipine or a pharmaceutically acceptable salt thereof is         comprised in a pharmaceutical unit dosage form suitable for the         oral administration of 2 to 10 mg (in particular 5 or 10 mg,         notably 5 mg) per day of amlodipine; and     -   hydrochlorothiazide or a pharmaceutically acceptable salt         thereof is comprised in a pharmaceutical unit dosage form         suitable for the oral administration of 5 to 25 mg (in         particular 12.5 mg or 25 mg) per day of hydrochlorothiazide.

In a sub-embodiment, aprocitentan is comprised in a pharmaceutical unit dosage form suitable for the oral administration of 12.5 mg or 25 mg per day of aprocitentan; valsartan or a pharmaceutically acceptable salt thereof is comprised in a pharmaceutical unit dosage form suitable for the oral administration of 160 mg per day of valsartan; amlodipine or a pharmaceutically acceptable salt thereof is comprised in a pharmaceutical unit dosage form suitable for the oral administration of 5 mg or 10 mg per day of amlodipine; and hydrochlorothiazide or a pharmaceutically acceptable salt thereof is comprised in a pharmaceutical unit dosage form suitable for the oral administration of 12.5 mg or 25 mg per day of hydrochlorothiazide; wherein each dosage combination, i.e. 12.5 mg/160 mg/5 mg/12.5 mg; 12.5 mg/160 mg/10 mg/12.5 mg; 12.5 mg/160 mg/5 mg/25 mg; 12.5 mg/160 mg/10 mg/25 mg; 25 mg/160 mg/5 mg/12.5 mg; 25 mg/160 mg/10 mg/12.5 mg; 25 mg/160 mg/5 mg/25 mg; and 25 mg/160 mg/10 mg/25 mg is explicitly disclosed.

“Angiotensin Receptor Blocker” or “ARB” in particular means in the present application valsartan, losartan, telmisartan, irbesartan, candesartan, olmesartan, azilsartan, or a pharmaceutically acceptable salt of one of these. A preferred ARB is valsartan or a pharmaceutically acceptable salt thereof.

“Calcium Channel Blocker” or “CCB” in particular means in the present application amlodipine, aranidipine, azelnidipine, barnidipine, benidipine, cilnidipine, clevidipine, isradipine, efonidipine, felodipine, lacidipine, lercanidipine, manidipine, nicardipine, nifedipine, nilvadipine, nimodipine, nisoldipine, nitrendipine, pranidipine, verapamil or diltiazem or a pharmaceutically acceptable salt of one of these. A preferred CCB is amlodipine or a pharmaceutically acceptable salt thereof.

“Diuretic” in particular means in the present application a diuretic of the thiazide class (a thiazide-like diuretic) such as especially chlorthalidone, hydrochlorothiazide, chlorothiazide, indapamide, or metolazone. Preferred diuretics are chlorthalidone or hydrochlorothiazide; thus one aspect of the present inventions relates to combinations of aprocitentan, the ARB valsartan, and the CCB amlodipine, with chlorthalidone; another aspect of the present invention relates to combinations of aprocitentan, the ARB valsartan, and the CCB amlodipine, with hydrochlorothiazide.

Further disclosed are, in addition, pharmaceutical compositions containing, as active principles, aprocitentan, or a pharmaceutically acceptable salt thereof, in combination with an Angiotensin Converting Enzyme inhibitor which is especially enalapril, or a pharmaceutically acceptable salt thereof, as well as at least one pharmaceutically acceptable excipient. “Angiotensin Converting Enzyme inhibitor” or “ACE inhibitor” in particular means in the present application captopril, enalapril, ramipril, quinapril, perindopril, lisinopril, imidapril or cilazapril, or a pharmaceutically acceptable salt of one of these. A preferred ACE inhibitor is enalapril or a pharmaceutically acceptable salt thereof.

8) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 17.8°, 20.0°, and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

9) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 17.8°, 18.6°, 20.0°, 23.2° and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

10) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 9.8°, 9.9°, 11.7°, 17.8°, 18.6°, 20.0°, 21.5°, 22.8°, 23.2° and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

11) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 9.8°, 9.9°, 11.7°, 14.5°, 15.4°, 15.6°, 16.9°, 17.2°, 17.8°, 18.6°, 19.9°, 20.0°, 21.5°, 21.9°, 22.8°, 23.2°, 23.5°, 24.9°, 25.1°, 25.3°, 25.6°, 25.9°, 27.1°, 27.3°, 28.5°, 29.0°, 29.4°, 30.1° and 30.6°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

12) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 9.8° (18%), 9.9° (18%), 11.7° (14%), 14.5° (10%), 15.4° (14%), 15.6° (29%), 16.9° (19%), 17.2° (16%), 17.8° (100%), 18.6° (50%), 19.9° (54%), 20.0° (67%), 21.5° (24%), 21.9° (10%), 22.8° (18%), 23.2° (49%), 23.5° (83%), 24.9° (32%), 25.1° (20%), 25.3° (24%), 25.6° (33%), 25.9° (16%), 27.1° (23%), 27.3° (39%), 28.5° (13%), 29.0° (23%), 29.4° (15%), 30.1° (12%) and 30.6° (10%); wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

The present data show peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parentheses) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported).

13) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form A which essentially shows the X-ray powder diffraction pattern as depicted in FIG. 1, wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

In this context the term “essentially” means that at least the major peaks of the diagram depicted in said figures, i.e. those having a relative intensity of more than 10%, especially more than 20%, as compared to the most intense peak in the diagram, have to be present. However, the person skilled in the art of X-ray powder diffraction will recognize that relative intensities in X-ray powder diffraction diagrams may be subject to strong intensity variations due to preferred orientation effects.

14) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form A obtainable by crystallisation of the COMPOUND in an aqueous solution at pH 6.2 to 6.8.

For avoidance of any doubt, whenever one of the above embodiments refers to “peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ”, said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and it should be understood that the accuracy of the 2θ values as provided herein is in the range of +/−0.1-0.2°. Notably, when specifying an angle of refraction 2theta (20) for a peak in the invention embodiments and the claims, the 2θ value given is to be understood as an interval from said value minus 0.2° to said value plus 0.2° (2θ+/−0.2°); and preferably from said value minus 0.1° to said value plus 0.1° (2θ+/−0.1°).

When defining the presence of peak in e.g. an X-ray powder diffraction diagram, a common approach is to do this in terms of the S/N ratio (S=signal, N=noise). According to this definition, when stating that a peak has to be present in an X-ray powder diffraction diagram, it is understood that the peak in the X-ray powder diffraction diagram is defined by having an S/N ratio (S=signal, N=noise) of greater than x (x being a numerical value greater than 1), usually greater than 2, especially greater than 3.

Unless used regarding temperatures, the term “about” placed before a numerical value “X” refers in the current application to an interval extending from X minus 10% of X to X plus 10% of X, and preferably to an interval extending from X minus 5% of X to X plus 5% of X. In the particular case of temperatures, the term “about” placed before a temperature “Y” refers in the current application to an interval extending from the temperature Y minus 10° C. to Y plus 10° C., preferably to an interval extending from Y minus 5° C. to Y plus 5° C., notably to an interval extending from Y minus 3° C. to Y plus 3° C. Room temperature means a temperature of about 25° C. When in the current application the term n equivalent(s) is used wherein n is a number, it is meant and within the scope of the current application that n is referring to about the number n, preferably n is referring to the exact number n.

Whenever the word “between” or “to” is used to describe a numerical range, it is to be understood that the end points of the indicated range are explicitly included in the range. For example: if a temperature range is described to be between 40° C. and 80° C. (or 40° C. to 80° C.), this means that the end points 40° C. and 80° C. are included in the range; or if a variable is defined as being an integer between 1 and 4 (or 1 to 4), this means that the variable is the integer 1, 2, 3, or 4.

15) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form C characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 9.7°, 15.7°, and 22.0°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

16) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form C characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 7.8°, 9.7°, 15.7°, 19.8° and 22.0°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

17) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form C characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 7.8°, 9.7°, 15.7°, 17.2°, 17.8°, 18.8°, 19.8°, 22.0°, 23.6°, and 25.3°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

18) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form C characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 7.8°, 9.7°, 15.7°, 17.2°, 17.8°, 18.8°, 19.8°, 20.1°, 20.6°, 21.6°, 22.0°, 23.4°, 23.6°, 24.1°, 24.5°, 25.1°, 25.3°, 25.7°, 26.8°, 27.1°, 28.5°, 30.8° and 30.8°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

19) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form C characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 7.8° (23%), 9.7° (42%), 15.7° (37%), 17.2° (16%), 17.8° (15%), 18.8° (26%), 19.8° (71%), 20.1° (51%), 20.6° (15%), 21.6° (15%), 22.0° (100%), 23.4° (27%), 23.6° (40%), 24.1° (23%), 24.5° (16%), 25.1° (13%), 25.3° (39%), 25.7° (28%), 26.8° (19%), 27.1° (16%), 28.5° (31%), 30.8° (13%) and 30.8° (13%); wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

The present data show peaks having a relative intensity, as compared to the most intense peak in the diagram, of the following percentages (relative peak intensitites given in parentheses) at the indicated angles of refraction 2theta (selected peaks from the range 3-33° 2theta with relative intensity larger then 10% are reported).

20) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form C which essentially shows the X-ray powder diffraction pattern as depicted in FIG. 3, wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.

In this context the term “essentially” means that at least the major peaks of the diagram depicted in said figures, i.e. those having a relative intensity of more than 10%, especially more than 20%, as compared to the most intense peak in the diagram, have to be present. However, the person skilled in the art of X-ray powder diffraction will recognize that relative intensities in X-ray powder diffraction diagrams may be subject to strong intensity variations due to preferred orientation effects.

21) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in crystalline Form C obtainable by crystallisation of the COMPOUND from MeOH, EtOH or propan-2-ol.

22) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 7), said composition comprising aprocitentan in amorphous form. Such amorphous form may be obtained by milling form A. For Example, the amorphous form is obtainable by milling in a ball mill (MM200 Retsch Ball Mill, 2 agate beads), 30 min at 30 Hz at ambient temperature.

The production of the pharmaceutical compositions can be effected in a manner which will be familiar to any person skilled in the art (see for example Remington, The Science and Practice of Pharmacy, 21st Edition (2005), Part 5, “Pharmaceutical Manufacturing” [published by Lippincott Williams & Wilkins]) by bringing the crystalline forms of the present invention, optionally in combination with other therapeutically valuable substances, into a galenical administration form together with suitable, non-toxic, inert, pharmaceutically acceptable solid or liquid carrier materials and, if desired, usual pharmaceutical adjuvants.

23) A further embodiment relates to a solid pharmaceutical composition (in particular in the form of a tablet) according to any one of embodiments 1) to 22), especially according to any one of embodiments 8) to 14), or according to any one of embodiments 15) to 21), comprising as pharmaceutically acceptable excipient inert microcrystalline cellulose, lactose, hydroxypropylcellulose, croscarmellose sodium and magnesium stearate.

24) Especially, the solid pharmaceutical composition of embodiment 23) will comprise aprocitentan in a total amount from 5 to 25% in weight based on the total weight of the pharmaceutical composition, microcrystalline cellulose in a total amount from 2θ to 30% in weight based on the total weight of the pharmaceutical composition, lactose in a total amount from 40 to 65% in weight based on the total weight of the pharmaceutical composition, hydroxypropylcellulose in a total amount from 1 to 3% in weight based on the total weight of the pharmaceutical composition, croscarmellose sodium in a total amount from 2 to 8% in weight based on the total weight of the pharmaceutical composition and magnesium stearate in a total amount from 0.2 to 2% in weight based on the total weight of the pharmaceutical composition, whereby the total percent in weight of the solid pharmaceutical composition will always be 100; the aforementioned solid pharmaceutical composition will particularly be in the form of a tablet.

25) A further embodiment of the invention relates to a pharmaceutical composition according to embodiments 23) to 24), wherein said pharmaceutical composition is in form of a tablet. In a sub-embodiment, the pharmaceutically active ingredients are comprised in granules prior to compression to said tablet.

A tablet according to embodiment 25) can optionally be coated with a suitable protective pellicle. Said protective pellicle will notably prevent direct contact of the pharmaceutical composition with moisture; it may also ease imprints that may be desired to be used in order to distinguish the pharmaceutical composition from others.

The coating material for making such protective pellicle may include a low water vapour permeability polymer (such as a polyvinyl alcohol (e.g. Aquapolish® white PVA from manufacturer Biogrund) or dimethylaminoethyl methacrylate (e.g. EUDRAGIT® E P0)). The coating material can further include a plasticizing agent (e.g. propylene glycol, triacetyne, dibutyl phthalate or dibutyl sebacate), a surfactant (e.g. sodium lauryl sulphate or a polysorbate such as Tween®) and/or a lubricant/glidant (e.g. stearic acid, magnesium or calcium stearate or talc). Moreover, the coating material can also include a pigment (e.g. iron(II) oxide, iron(III) oxide or titanium oxide) to give the tablet a coloured aspect.

26) A further embodiment of the invention relates to a pharmaceutical composition according to any one of embodiments 23) to 24), wherein said pharmaceutical composition is in form of a capsule. In a sub-embodiment, the pharmaceutically active ingredients are comprised in granules prior to filling into said capsules.

For avoidance of any doubt, the invention further relates to the crystalline forms of aprocitentan, especially to crystalline form A, disclosed herein wherein such crystalline form is suitable/is used as final isolation step of aprocitentan (e.g. in order to meet the purity requirements of pharmaceutical production), whereas the final pharmaceutical composition according to embodiments 1 to 26) may or may not contain said crystalline form (e.g. because the originally crystalline form of aprocitentan is further transformed during the manufacturing process and/or is dissolved in the pharmaceutically acceptable carrier material(s); thus, in the final pharmaceutical composition, aprocitentan may be present in non-crystalline form, in another crystalline form, or in dissolved form, or the like).

Such combination pharmaceutical compositions according to embodiments 1) to 26) are especially useful for the treatment of endothelin related diseases including hypertension, pulmonary hypertension, coronary diseases, cardiac insufficiency, renal and myocardial ischemia, renal failure, cerebral ischemia, dementia, migraine, subarachnoidal hemorrhage, Raynaud's syndrome, digital ulcers or portal hypertension as well as for the treatment or prevention of atherosclerosis, restenosis after balloon or stent angioplasty, inflammation, stomach and duodenal ulcer, cancer, melanoma, prostate cancer, prostatic hypertrophy, erectile dysfunction, hearing loss, amaurosis, chronic bronchitis, asthma, pulmonary fibrosis, gram negative septicemia, shock, sickle cell anemia, glomerulonephritis, renal colic, glaucoma, connective tissue diseases, diabetic complications, complications of vascular or cardiac surgery or after organ transplantation, complications of cyclosporin treatment, pain or hyperlipidemia.

The combination pharmaceutical compositions according to embodiments 1) to 26) are also useful for the treatment of Chronic Kidney Disease (CKD), especially CKD of stages 1 to 4 as defined by the Kidney Disease Improving Global Outcomes (KDIGO) Guidelines (and notably CKD of stage 3), and in particular CKD of these stages caused by essential hypertension.

The pharmaceutical compositions according to embodiments 1) to 26) are especially useful for the treatment of hypertension related diseases comprising hypertension including especially difficult to treat/resistant hypertension; pulmonary hypertension; heart failure including especially chronic heart failure; reducing the risk of developing a major cardiovascular event (such as heart failure, myocardial infarction, stroke, or death from cardiovascular causes) in patients who are at cardiovascular risk (such as patients who have coronary artery disease and/or patients who have demonstrated clinical signs of congestive heart failure); angina pectoris; and diastolic dysfunction; erectile dysfunction; CKD (especially CKD of stages 1 to 4 as defined by the Kidney Disease Improving Global Outcomes (KDIGO) Guidelines (and notably CKD of stage 3), and in particular CKD of these stages caused by/associated with essential hypertension, especially resistant hypertension); and diabetes, and diabetes related diseases such as diabetic arteriopathy, diabetic nephropathy, diabetic retinopathy, diabetic vasculopathy; and reducing the risk of developing a major cardiovascular event (such as heart failure, myocardial infarction, stroke, or death from cardiovascular causes) in patients who have diabetes that is accompanied by at least one other cardiovascular risk factor (such as hypertension, especially resistant hypertension).

Preferably, the pharmaceutical compositions according to embodiments 1) to 26) are useful for in the treatment of certain endothelin related diseases, which may be defined as a disease selected from the group consisting of hypertension, pulmonary hypertension, diabetic arteriopathy, heart failure, erectile dysfunction, angina pectoris and CKD (especially CKD of stages 1 to 4 as defined by the Kidney Disease Improving Global Outcomes (KDIGO) Guidelines (and notably CKD of stage 3), and in particular CKD of these stages caused by essential hypertension).

Moreover, the pharmaceutical compositions according to embodiments 1) to 19) are useful in the treatment of a disease selected from the group consisting of essential hypertension, resistant hypertension, pulmonary hypertension and pulmonary arterial hypertension (and notably in the treatment of resistant hypertension).

Essential hypertension (also called primary hypertension or idiopathic hypertension) is the form of hypertension that by definition has no identifiable cause. It represents a significant global public health concern, contributing to vascular and renal morbidity and to cardiovascular mortality. The diagnosis of essential hypertension is made when the average of multiple systolic blood pressure measurements on 2 or more subsequent visits is consistently equal to or above a certain threshold value T_(SBP). Individuals with high normal blood pressure tend to maintain pressures that are above average for the general population and are at greater risk for development of definite hypertension and cardiovascular events than the general population. The threshold value T_(SBP) above which treatment is recommended is regularly discussed among clinicians (see e.g. Mancia et al, J. Hypertens. (2013), 31, 1281-1357); accordingly, depending on the patient's general condition and age, T_(SBP) could be 140 or 130 mm Hg, or another suitable value.

The term “resistant hypertension” [equivalent to the term “difficult to treat hypertension”] in the present invention is defined as blood pressure that remains above goal in spite of the concurrent use of 3 antihypertensive agents of different classes. One of the 3 agents should be a diuretic and all agents should be prescribed at optimal/maximal dose amounts. As defined, resistant hypertension patients include patients whose blood pressure is controlled with use of more than 3 medications. That is, patients whose blood pressure is controlled but require 4 or more medications to do so should be considered resistant to treatment (see e.g. Mancia et al, J. Hypertens. (2013), 31, 1281-1357).

27) A fourth aspect of the invention thus relates to aprocitentan, or a pharmaceutically acceptable salt thereof, for use in the treatment of hypertension, pulmonary hypertension, diabetic arteriopathy, heart failure, erectile dysfunction, angina pectoris and chronic kidney disease (notably in the treatment of resistant hypertension), wherein aprocitentan is to be administered in combination with an angiotenin receptor blocker which is especially valsartan, or a pharmaceutically acceptable salt thereof.

28) A further embodiment relates to aprocitentan, or a pharmaceutically acceptable salt thereof, for use in the treatment of hypertension, pulmonary hypertension, diabetic arteriopathy, heart failure, erectile dysfunction, angina pectoris and chronic kidney disease (notably in the treatment of resistant hypertension), wherein aprocitentan is to be administered in combination with

-   -   an angiotenin receptor blocker which is especially valsartan, or         a pharmaceutically acceptable salt thereof, and     -   a calcium channel blocker which is especially amlodipine, or a         pharmaceutically acceptable salt thereof.

29) A further embodiment relates to aprocitentan, or a pharmaceutically acceptable salt thereof, for use in the treatment of hypertension, pulmonary hypertension, diabetic arteriopathy, heart failure, erectile dysfunction, angina pectoris and chronic kidney disease (notably in the treatment of resistant hypertension), wherein aprocitentan is to be administered in combination with

-   -   an angiotenin receptor blocker which is especially valsartan or         a pharmaceutically acceptable salt thereof,     -   a calcium channel blocker which is especially amlodipine, or a         pharmaceutically acceptable salt thereof; and     -   a diuretic which is a thiazide-like diuretic (notably         hydrochlorothiazide or chlorthalidone, especially         hydrochlorothiazide), or a pharmaceutically acceptable salt         thereof.

30) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 26) for use in the treatment of hypertension, pulmonary hypertension, diabetic arteriopathy, heart failure, erectile dysfunction, angina pectoris and chronic kidney disease (notably in the treatment of resistant hypertension).

31) A further embodiment relates to aprocitentan, or a pharmaceutically acceptable salt thereof, for use in the treatment of hypertension including resistant hypertension; heart failure including chronic heart failure; diastolic dysfunction; CKD including CKD of stage 3 caused by or associated with essential hypertension; or for the reduction of the risk of developing a major cardiovascular event in patients who have diabetes that is accompanied by at least one other cardiovascular risk factor comprising hypertension, wherein aprocitentan is to be administered in combination with

-   -   an angiotenin receptor blocker which is especially valsartan or         a pharmaceutically acceptable salt thereof,     -   a calcium channel blocker which is especially amlodipine, or a         pharmaceutically acceptable salt thereof; and     -   a diuretic which is a thiazide-like diuretic (notably         hydrochlorothiazide or chlorthalidone, especially         hydrochlorothiazide), or a pharmaceutically acceptable salt         thereof.

32) A further embodiment relates to aprocitentan, or a pharmaceutically acceptable salt thereof, for use according to embodiments 29) or 31), wherein the angiotenin receptor blocker is valsartan or a pharmaceutically acceptable salt thereof; the calcium channel blocker is amlodipine, or a pharmaceutically acceptable salt thereof; and the diuretic is hydrochlorothiazide or a pharmaceutically acceptable salt thereof, or chlorthalidone or a pharmaceutically acceptable salt thereof.

33) A further embodiment relates to aprocitentan, or a pharmaceutically acceptable salt thereof, for use according to embodiment 32) wherein the diuretic is hydrochlorothiazide.

34) A further embodiment relates to aprocitentan, or a pharmaceutically acceptable salt thereof, for use according to embodiments 32) or 33), wherein, mutatis mutandis, the pharmaceutically active ingredients are to be administered in a dosage as disclosed in embodiments 5) or 7).

35) Another embodiment relates to aprocitentan or a pharmaceutically acceptable salt thereof; to be administered in combination as defined in any one of embodiments 27) to 29), or 31) to 34); or to a pharmaceutical composition comprising aprocitentan or a pharmaceutically acceptable salt thereof, as defined in any one of embodiments 1) to 26); for use in the treatment of a disorder selected from the group consisting of chronic kidney disease (CKD), diabetes, diabetic nephropathy, diabetic retinopathy, diabetic vasculopathy, chronic heart failure and diastolic dysfunction.

36) One sub-embodiment of embodiment 35) relates to aprocitentan or a pharmaceutically acceptable salt thereof, for use in the treatment of CKD, especially CKD of stages 1 to 4 as defined by the Kidney Disease Improving Global Outcomes (KDIGO) Guidelines (and notably CKD of stage 3), and in particular CKD of these stages caused by essential hypertension.

37) Another sub-embodiment of embodiment 35) relates to aprocitentan or a pharmaceutically acceptable salt thereof, for use in the treatment of diabetes (that is, type 1 or type 2 diabetes).

38) Another sub-embodiment of embodiment 35) relates to aprocitentan or a pharmaceutically acceptable salt thereof, for use in the treatment of diabetic nephropathy.

39) Another sub-embodiment of embodiment 35) relates to aprocitentan or a pharmaceutically acceptable salt thereof, for use in the treatment of diabetic retinopathy.

40) Another sub-embodiment of embodiment 35) relates to aprocitentan or a pharmaceutically acceptable salt thereof, for use in the treatment of diabetic vasculopathy.

41) Another sub-embodiment of embodiment 35) relates to aprocitentan or a pharmaceutically acceptable salt thereof, for use in the treatment of chronic heart failure.

42) According to one variant of sub-embodiment 41), the chronic heart failure of sub-embodiment 47) will be heart failure with preserved ejection fraction.

43) According to another variant of sub-embodiment 41), the chronic heart failure of sub-embodiment 47) will be diastolic heart failure.

44) Another sub-embodiment of embodiment 35) relates to aprocitentan or a pharmaceutically acceptable salt thereof, for use in the treatment of diastolic dysfunction.

Accordingly, aprocitentan or a pharmaceutically acceptable salt thereof according is for use in combination with said further pharmaceutically active ingredients. The corresponding combined treatment may be effected simultaneously, separately, or over a period of time (especially simultaneously).

“Simultaneously”, when referring to an administration type, means in the present application that the administration type concerned consists in the administration of two or more active ingredients and/or treatments at approximately the same time; wherein it is understood that a simultaneous administration will lead to exposure of the subject to the two or more active ingredients and/or treatments at the same time. When administered simultaneously, said two or more active ingredients may be administered in a fixed dose combination, or in an equivalent non-fixed dose combination (e.g. by using two or more different pharmaceutical compositions to be administered by the same route of administration at approximately the same time), or by a non-fixed dose combination using two or more different routes of administration; wherein said administration leads to essentially simultaneous exposure of the subject to the two or more active ingredients and/or treatments. For example, when used in combination with an ARB and/or CCB, and, if present, with a diuretic, the COMPOUND would possibly be used “simultaneously”.

“Fixed dose combination”, when referring to an administration type, means in the present application that the administration type concerned consists in the administration of one single pharmaceutical composition comprising the two or more active ingredients, such as especially the pharmaceutical compositions of embodiments 1) to 26).

“Separately”, when referring to an administration type, means in the present application that the administration type concerned consists in the administration of two or more active ingredients and/or treatments at different points in time; wherein it is understood that a separate administration will lead to a treatment phase (e.g. at least 1 hour, notably at least 6 hours, especially at least 12 hours) where the subject is exposed to the two or more active ingredients and/or treatments at the same time; but a separate administration may also lead to a treatment phase where for a certain period of time (e.g. at least 12 hours, especially at least one day) the subject is exposed to only one of the two or more active ingredients and/or treatments. Separate administration especially refers to situations wherein at least one of the active ingredients and/or treatments is given with a periodicity substantially different from daily (such as once or twice daily) administration (e.g. wherein one active ingredient and/or treatment is given e.g. once or twice a day, and another is given e.g. every other day, or once a week or at even longer distances).

By administration “over a period of time” is meant in the present application the subsequent administration of two or more active ingredients and/or treatments at different times. The term in particular refers to an administration method according to which the entire administration of one of the active ingredients and/or treatments is completed before the administration of the other/the others begins. In this way it is possible to administer one of the active ingredients and/or treatments for several months before administering the other active ingredient(s) and/or treatment(s).

45) A further embodiment relates to a pharmaceutical composition according to any one of embodiments 1) to 26) for use in the treatment of hypertension including resistant hypertension; heart failure including chronic heart failure; diastolic dysfunction; CKD including CKD of stage 3 caused by or associated with essential hypertension; or for the reduction of the risk of developing a major cardiovascular event in patients who have diabetes that is accompanied by at least one other cardiovascular risk factor comprising hypertension.

It is understood that any embodiment relating to aprocitentan, or a pharmaceutically acceptable salt thereof, for use in the treatment of certain endothelin related diseases, wherein aprocitentan is to be administered in combination with further active ingredients such as:

-   -   an angiotenin receptor blocker which is especially valsartan or         a pharmaceutically acceptable salt thereof; or     -   an angiotenin receptor blocker which is especially valsartan or         a pharmaceutically acceptable salt thereof; and a calcium         channel blocker which is especially amlodipine, or a         pharmaceutically acceptable salt thereof; or     -   an angiotenin receptor blocker which is especially valsartan or         a pharmaceutically acceptable salt thereof; a calcium channel         blocker which is especially amlodipine, or a pharmaceutically         acceptable salt thereof; and a diuretic which is a thiazide-like         diuretic (notably hydrochlorothiazide or chlorthalidone,         especially hydrochlorothiazide), or a pharmaceutically         acceptable salt thereof;

such embodiment also relates to such further active ingredients to be administered in combination with aprocitentan, or a pharmaceutically acceptable salt thereof; to the use of aprocitentan for the manufacture of a pharmaceutical composition comprising aprocitentan and said further active ingredients; to the use of a pharmaceutical composition comprising aprocitentan and such further active ingredients for the treatment of such diseases; and to a method of treating said diseases comprising administering to a subject (preferably a human) in need thereof an effective amount of aprocitentan to be administered in combination with said further active ingredients, or comprising administering to a subject in need thereof an effective amount of a pharmaceutical composition comprising aprocitentan and said further active ingredients as disclosed herein.

46) A further embodiment relates to a method for the treatment of hypertension, pulmonary hypertension, diabetic arteriopathy, heart failure, erectile dysfunction, angina pectoris and chronic kidney disease (notably in the treatment of resistant hypertension);

comprising the administration of a pharmaceutically effective amount of aprocitentan, or of a pharmaceutically acceptable salt thereof, to a subject in need thereof, wherein aprocitentan is administered in combination with

-   -   a pharmaceutically effective amount of an angiotenin receptor         blocker which is especially valsartan or a pharmaceutically         acceptable salt thereof,     -   a pharmaceutically effective amount of a calcium channel blocker         which is especially amlodipine, or a pharmaceutically acceptable         salt thereof; and     -   a pharmaceutically effective amount of a diuretic which is a         thiazide-like diuretic (notably hydrochlorothiazide or         chlorthalidone, especially hydrochlorothiazide), or a         pharmaceutically acceptable salt thereof.

47) A further embodiment relates to a method for the treatment of hypertension, pulmonary hypertension, diabetic arteriopathy, heart failure, erectile dysfunction, angina pectoris and chronic kidney disease (notably in the treatment of resistant hypertension); comprising the administration of a pharmaceutical composition according to any one of embodiments 1) to 26).

48) A further embodiment relates to a method for the treatment of hypertension including resistant hypertension; heart failure including chronic heart failure; diastolic dysfunction; CKD including CKD of stage 3 caused by or associated with essential hypertension; or for the reduction of the risk of developing a major cardiovascular event in patients who have diabetes that is accompanied by at least one other cardiovascular risk factor comprising hypertension;

comprising the administration of a pharmaceutically effective amount of aprocitentan, or of a pharmaceutically acceptable salt thereof, to a subject in need thereof, wherein aprocitentan is administered in combination with

-   -   a pharmaceutically effective amount of an angiotenin receptor         blocker which is especially valsartan or a pharmaceutically         acceptable salt thereof,     -   a pharmaceutically effective amount of a calcium channel blocker         which is especially amlodipine, or a pharmaceutically acceptable         salt thereof; and     -   a pharmaceutically effective amount of a diuretic which is a         thiazide-like diuretic (notably hydrochlorothiazide or         chlorthalidone, especially hydrochlorothiazide), or a         pharmaceutically acceptable salt thereof;

49) A further embodiment relates to a method for the treatment of hypertension including resistant hypertension; heart failure including chronic heart failure; diastolic dysfunction; CKD including CKD of stage 3 caused by or associated with essential hypertension; or for the reduction of the risk of developing a major cardiovascular event in patients who have diabetes that is accompanied by at least one other cardiovascular risk factor comprising hypertension; comprising the administration of a pharmaceutical composition according to any one of embodiments 1) to 26).

50) A further embodiment relates to a method according to embodiments 46) or 48), wherein the angiotenin receptor blocker is valsartan or a pharmaceutically acceptable salt thereof; the calcium channel blocker is amlodipine, or a pharmaceutically acceptable salt thereof; and the diuretic is hydrochlorothiazide or a pharmaceutically acceptable salt thereof, or chlorthalidone or a pharmaceutically acceptable salt thereof.

51) A further embodiment relates to a method according to embodiment 50) wherein the diuretic is hydrochlorothiazide.

52) A further embodiment relates to a method according to embodiments 50) or 51), wherein, mutatis mutandis, the pharmaceutically active ingredients are administered in a dosage as disclosed in embodiments 5) or 7).

Particular embodiments of the invention are described in the following Examples, which serve to illustrate the invention in more detail without limiting its scope in any way.

Experimental Procedures Abbreviations:

The following abbreviations are used throughout the specification and the examples:

Ac acetyl AcOH acetic acid aq. aqueous DCM dichloromethane DMSO dimethylsulfoxide EtOAc ethyl acetate eq. equivalent(s)

FTIR Fourier Transform Infrared Spectroscopy or Spectrum HPLC High Performance Liquid Chromatography

iPrOAc isopropyl acetate MeOH methanol MIBK methyl iso-butyl ketone org. organic rt room temperature THF tetrahydrofuran vol. volume(s) w/w weight-per-weight ratio wt. weight unit XRPD X-ray powder diffraction

EXAMPLES Method for Obtaining XRPD Patterns

All XRPD patterns for the solid forms described herein have been obtained as described hereafter. X-ray powder diffraction patterns were collected on a Bruker D8 Advance X-ray diffractometer equipped with a Lynxeye detector operated with CuKα-radiation in reflection mode (coupled two Theta/Theta). Typically, the X-ray tube was run at of 40 kV/40 mA. A step size of 0.02° (2θ) and a step time of 76.8 sec over a scanning range of 3-50° in 2θ were applied. The divergence slit was set to fixed 0.3. Powders were slightly pressed into a silicon single crystal sample holder with depth of 0.5 mm and samples were rotated in their own plane during the measurement. Diffraction data are reported using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping. The accuracy of the 2θ values as provided herein is in the range of +/−0.1-0.2° as it is generally the case for conventionally recorded X-ray powder diffraction patterns.

Example 1: Form A

1.1. A 3 L double jacketed reactor was charged with 5-(4-bromophenyl)-4-(2-((5-bromopyrimidin-2-yl)oxy)ethoxy)-6 fluoropyrimidine (100 g, 0.213 mol, 1 eq.), sulfamide (40.9 g, 0.425 mol, 2.0 eq.), K₂CO₃ (147 g, 1.06 mol, 5 eq.) and DMSO (500 mL, 5 vol.) doped with water (2 mL, 0.111 mol, 0.5 eq.). The heterogeneous mixture was heated to 70° C. during ca. 3 h, after which time complete conversion was observed. After cooling to 20° C., most of the inorganic salt freight was removed by filtration. The filter cake was washed with EtOAc/iPrOAc 1:1 (300 mL, 3 vol.). Celite (100 g, 1 wt.) topped with a layer of charcoal (20 g, 0.2 wt.) was preconditioned with EtOAc/iPrOAc 1:1 (500 mL, 5 vol.) (filtrate discarded). The reaction mixture was filtered over this cake and rinsed with EtOAc/iPrOAc 1:1 (300 mL, 3 vol.). Then 1M aq. NaOAc solution (500 mL, 0.5 mol, 2.3 eq, 5 vol.) was added while keeping the temperature at 25-35° C. The aq. phase was washed a second time with EtOAc/iPrOAc 1:1 (500 mL, 5 vol.). To the aq. phase, 1M H₂SO₄ (200 mL, 0.2 mol, 1 eq., 2 vol.) was added during 1 h at 25-30° C. Crystallization started at pH 8.5-8.0. The crude product was filtered off as XRPD pattern form K (DMSO solvate) or a mixture of form A and form K. It was washed twice with water (2×1000 mL, 2×10 vol.). The solid was slurried in water (1000 mL, 10 vol.) at rt for 3 h. The solid was filtered off and slurried a second time in water (1000 mL, 10 vol.) at rt for 3 h. After washing with water (1000 mL, 10 vol.), the pure product was dried in vacuum at 40° C. to afford {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide as a white to off-white solid (75 g, 65% yield, XRPD pattern form A).

1.2. A reactor (200 L Hastelloy) was charged with 5-(4-bromophenyl)-4-(2-((5-bromopyrimidin-2-yl)oxy)ethoxy)-6 fluoropyrimidine (24.2 kg, 51.5 mol), sulfamide (9.7 kg, 100.9 mol, 1.96 eq.), potassium carbonate (35.5 kg, 256.9 mol, 5.0 eq.), DMSO (133 kg, 5 vol.) and water (490 g, 27.2 mol, 0.53 eq.). The contents of the reactor were heated to 70-75° C. Monitoring by HPLC showed complete conversion in 4 hours. The contents were cooled to 20-25° C. and the solids were centrifuged off. Each load was washed with EtOAc/iPrOAc 1:1 (65 kg, 3 vol.). The filtrate was re-charged in the reactor and charcoal (2.4 kg, 10% w/w) and Celite® (4.8 kg, 20% w/w) were added. The contents were agitated for 1 h at 15-20° C. and filtered through a cartridge filter back into the reactor. The filters were rinsed with EtOAc/iPrOAc 1:1 (43 kg, 2 vol.). NaOAc (8% in water) (124 kg, 5 vol.) was added over 2 h, keeping the temperature below 25° C. After phase separation, the aq. layer was washed with EtOAc/iPrOAc 1:1 (109 kg, 5 vol.) at 20-25° C. Sulfuric acid (5% in water; 64 L, 32.6 mol, 0.63 eq.) was added to the aq. layer at 25-30° C. over 2 hours to reach pH 6.4. The contents were then cooled to 15-20° C. for 1 h. The solids were filtered off and washed twice with water (2×24 L, 2×1 vol.). The solid was slurried twice in water (2×242 kg, 2×10 vol.) at 15-20° C. for 3 hours each, filtered and dried, to yield 5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide as a white solid (21.6 g, 77% yield, XRPD pattern Form A).

Example 2: Form B (DCM Solvate of the Compound)

5-(4-bromophenyl)-4-(2-((5-bromopyrimidin-2-yl)oxy)ethoxy)-6 fluoropyrimidine (10.0 g, 21.3 mmol, 1.00 eq.), sulfamide (4.1 g, 42.5 mmol, 2.0 eq.) and K₂CO₃ (14.7 g, 106 mmol, 5.0 eq.) were suspended in DMSO (50 mL, 5 vol.) and heated to 70° C. for 5 h. The mixture was cooled to rt and EtOAc (40 mL, 4 vol.) followed by water (100 mL, 10 vol.) were added. After separation of the layers (org. phase discarded), the aq. phase was extracted with DCM (100 mL, 10 vol.). The DCM layer was acidified from pH 11.5 to pH 7.0 with conc. AcOH (3 mL, 52 mmol, 2.5 eq.), resulting in crystallization of the product. The suspension was cooled to 0° C. for 1 h, then to −5° C. for 15 min. The solid was filtered, washed with cold DCM (10 mL, 1 vol.) and dried to yield a DCM solvate of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form B as a white solid (9.8 g, 84% yield).

Example 3: Form C

0.2 mL of a stock solution of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide dissolved in THF at 50 mg/mL was dispensed to 3 vials. The solvent was evaporated for 90 min in a Combidancer device from Hettich AG (Bach, Switzerland) operated at 35° C. and 200 mbar. Immediately thereafter 0.015 mL of MeOH for the first vial, EtOH for the second vial and iPrOH for the third vial was added and the vials were allowed to stand closed for 3 days. Solid residue of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form C was obtained for each of these solvents.

Example 4: Form D

4.1. A reactor was charged with sulfamide (2.00 eq.), K₂CO₃ (5.00 eq.), 5-(4-bromophenyl)-4-(2-((5-bromopyrimidin-2-yl)oxy)ethoxy)-6-fluoropyrimidine (1.00 eq.), DMSO (5.0 vol.) and water (0.02 vol.). The mixture was heated to 75° C. for 2 h. After cooling to 23° C., the suspension was filtered and rinsed with EtOAc/iPrOAc 1:1 (5.5 vol.) through the reactor. The filtrate was again filtered through an in-line filter and rinsed with EtOAc/iPrOAc 1:1 (1.5 vol.). A solution of 1M NaOAc in water (5.0 vol.) was added at 27° C., and the layers were separated. The aq. phase was washed with EtOAc/iPrOAc 1:1 (5.0 vol.). The aq. phase was acidified to pH 5.8 using 0.5M H₂SO₄ in water (2.35 vol.) over 2.5 h, leading to crystallization. After 1 h stirring at 20° C., the suspension was filtered and washed with water (2×10 vol.). The solid was slurried twice in water (2×10 vol.) at 20° C. for 3 h each, filtered, washed with water (10 vol.) and dried to give {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form D.

4.2. 50 mg of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form A was dissolved in 3 mL methyl-ethylketone in a new 7 mL glass vial. After sonication in an ultrasound bath for 1 min, the vial was allowed to stand open at rt for 3 days. The solid residue was {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form D.

Example 5: Form E (MeCN Solvate of the Compound)

{5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form A was heated to reflux in 10 volumes of MeCN. After 10 min it was allowed to cool down to 20° C. within 1 h (heating bath removed). It was filtered off and dried under reduced pressure and 45° C. Solid residue was a MeCN solvate of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form E.

Example 6: Form J

The DCM solvate of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide Form B (9.4 g, 17.2 mmol, 1.00 eq.) was dissolved in DMSO (19 mL, 2 vol.). The solution was added into H₂O (94 mL, 10 vol.) and stirred at rt for 5 min. The resulting suspension was filtered, washed twice with H₂O (2×94 mL, 2×10 vol.) and dried to provide {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide Form J as a white solid (6.8 g, 72% yield).

Example 7: Form K (DMSO Solvate of the Compound)

7.1. {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide Form A (1.00 g, 1.83 mmol, 1.00 eq.) was dissolved in DMSO (2 mL, 2 vol.). To this solution, 10% H₂O in DMSO (10 mL, 10 vol.) was added slowly, followed by pure H₂O (2 mL, 2 vol.). Seeding with form K triggered crystallization of the product. The suspension was filtered, washed with H₂O (5×10 mL, 5×10 vol.) and dried to give a DMSO solvate {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form K as a white solid (0.95 g, 95% yield).

7.2. 5-(4-bromophenyl)-4-(2-((5-bromopyrimidin-2-yl)oxy)ethoxy)-6-fluoropyrimidine (10.0 g, 21.3 mmol, 1.00 eq.), sulfamide (4.1 g, 42.5 mmol, 2.0 eq.) and K₂CO₃ (14.7 g, 106 mmol, 5.0 eq.) were suspended in DMSO (50 mL, 5 vol.) and heated to 50° C. for 2θ h. The mixture was cooled to rt and MIBK (100 mL, 10 vol.) followed by water (100 mL, 10 vol.) were added. After separation of the layers (org. phase discarded), the aq. phase was acidified from pH 11.4 to pH 6.5 with conc. AcOH (4 mL, 70 mmol, 3.3 eq.), resulting in crystallization of the product. The solid was filtered, washed with water (4×50 mL, 4×5 vol.) and dried to afford a DMSO solvate of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form K as a beige solid (10.4 g, 90% yield).

Example 8: Form L (EtOH Solvate of the Compound)

The DMSO solvate of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide Form K (100 mg, 0.183 mmol, 1.00 eq.) was slurried in EtOH (0.5 mL, 5 vol.) at rt for 4 h. The suspension was filtered, washed twice with H₂O (2×0.5 mL, 2×5 vol.) and dried to afford an EtOH solvate of {5-(4-bromo-phenyl)-6-[2-(5-bromo-pyrimidin-2-yloxy)-ethoxy]-pyrimidin-4-yl}-sulfamide in Form L as a white solid (40 mg, 40% yield).

Example 9: ACT-132577 Tablets

Tablets containing each 50 mg of ACT-132577 can be prepared using a wet granulation process. The tablet composition is the following:

ACT-132577 tablets (250 mg) MATERIAL (CHEMICAL NAME) mg/tablet Weight %/tablet Intra- ACT-132577 (amorphous, solid 50.00 20.00 granular form A or solid form C, as described herein) Microcrystalline cellulose 61.50 24.60 Lactose (200M) 122.25 48.90 Hydroxypropylcellulose 5.50 2.20 Croscarmellose sodium 4.50 1.80 Water qs qs Extra- Croscarmellose sodium 5.00 2.00 granular Magnesium stearate 1.25 0.50 Total 250.00 100.00 qs = quantity sufficient

Preferably, ACT-132577 Form A (as described herein) will be used for making the tablets.

Example 10: ACT-132577 Tablets

The tablets of Example 9 can be coated with a layer of Aquapolish® white MS or Aquapolish® white PVA (coating manufacturer: Biogrund).

Example 11: ACT-132577 Tablets

Tablets containing each 50 mg of ACT-132577 can be prepared using a wet granulation process. The tablet composition is the following:

ACT-132577 tablets (250 mg) MATERIAL (CHEMICAL NAME) mg/tablet Weight %/tablet Intra- ACT-132577 (amorphous, solid 50.00 20.00 granular form A or solid form C, as described herein) Microcrystalline cellulose 61.25 24.50 Lactose (200M) 122.50 49.00 Hydroxypropylcellulose 5.00 2.00 Croscarmellose sodium 5.00 2.00 Water qs qs Extra- Croscarmellose sodium 5.00 2.00 granular Magnesium stearate 1.25 0.50 Total 250.00 100.00 qs = quantity sufficient

Preferably, ACT-132577 Form A (as described herein) will be used for making the tablets.

Example 12

The tablets of Example 11 can be coated with a layer of Aquapolish® white MS or Aquapolish® white PVA (coating manufacturer: Biogrund).

Example 13: ACT-132577 Tablets

Tablets containing each 12.5 mg of ACT-132577 can be prepared using a wet granulation process. The tablet composition is the following:

ACT-132577 tablets (100 mg) Material (Chemical name) mg/tablet Weight %/tablet Intra- ACT-132577 (amorphous, solid 12.50 12.50 granular form A or solid form C, as described herein) Microcrystalline cellulose 27.00 27.00 Lactose (200M) 54.00 54.00 Hydroxypropylcellulose 2.00 2.00 Croscarmellose sodium 2.00 2.00 Water qs qs Extra- Croscarmellose sodium 2.00 2.00 granular Magnesium stearate 0.50 0.50 Total 100.00 100.00 qs = quantity sufficient

Preferably, ACT-132577 Form A (as described herein) will be used for making the tablets.

Example 14: ACT-132577 Tablets

The tablets of Example 13 can be coated with a layer of Aquapolish® white MS or Aquapolish® white PVA (coating manufacturer: Biogrund).

Example 15: ACT-132577 Tablets

Tablets containing each 12.5 mg of ACT-132577 can be prepared using a wet granulation process. The tablet composition is the following:

ACT-132577 tablets (100 mg) MATERIAL (CHEMICAL NAME) mg/tablet Weight %/tablet Intra- ACT-132577 (amorphous, solid 12.50 12.50 granular form A or solid form C, as described herein) Microcrystalline cellulose 27.50 27.50 Lactose (200M) 53.50 53.50 Hydroxypropylcellulose 2.20 2.20 Croscarmellose sodium 1.80 1.80 Water qs qs Extra- Croscarmellose sodium 2.00 2.00 granular Magnesium stearate 0.50 0.50 Total 100.00 100.00 qs = quantity sufficient

Preferably, ACT-132577 Form A (as described herein) will be used for making the tablets.

Example 16: ACT-132577 Tablets

The tablets of Example 15 can be coated with a layer of Aquapolish® white MS or Aquapolish® white PVA (coating manufacturer: Biogrund).

Properties of the Crystal Forms Example 17: Storage at Room Temperature

A sample of Form A crystals of the COMPOUND (as obtained according to Example 1 above) has been stored at a temperature of 20-25° C. at 92% relative humidity for 2 months. X-ray powder diffraction performed on that sample at the end of the 2 months showed that the sample was still consisting only in Form A crystals of the COMPOUND. The same result was obtained after storage for 8 weeks under the above conditions. HPLC control of the sample after 8 weeks storage revealed no significant change in peak area %, i.e. no significant degradation was observed under such conditions.

A sample of Form B crystals of a dichloromethane solvate of the COMPOUND (as obtained according to Example 2 above) has been stored in a closed vial (2θ mg of Form B crystals being placed in a closed 4 mL vial) at a temperature of 20-25° C. for about 3 weeks. X-ray powder diffraction performed on that sample at the end of the 3 weeks showed that the Form B crystals were transformed into Form A crystals of the COMPOUND.

A sample of Form K crystals of a dimethylsulfoxide solvate of the COMPOUND (as obtained according to Example 7 above) has been stored in a closed vial (2θ mg of Form K crystals being placed in a closed 4 mL vial) at a temperature of 20-25° C. for about 3 weeks. X-ray powder diffraction performed on that sample at the end of the 3 weeks showed that the Form K crystals were transformed into Form A crystals of the COMPOUND.

Example 18: Hygroscopicity

Form A is considered to be slightly hygroscopic as determined by gravimetric vapor sorption (GVS). Mass increase of a sample as obtained according to Example 1 in the first cycle from 40% r.h. to 80% r.h. corresponds to 0.4%. At 95% r.h. 2.2% moisture were taken up in a reversible way without hysteresis upon drying.

Examples of Therapeutic Uses of ACT-132577 Example A: Acute Effects of ACT-132577 in Dahl Salt-Sensitive Rats

The acute effects of ACT-132577 on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) were evaluated by means of telemetry in conscious, male hypertensive Dahl salt-sensitive rats (hereafter “Dahl-S rats”—see details about this model in Rapp, Hypertension (1982), 4, 753-763).

Elevated blood pressure is induced in Dahl-S rats by providing 1% sodium chloride in drinking water. Groups of 6-7 Dahl-S rats were used for the vehicle (7.5% gelatin aquous solution) and each dose of ACT-132577 tested (0.3, 1, 3, 10, 30, 100, and 300 mg/kg). Effects of ACT-132577 on HR and MAP were calculated for individual animals relative to the 24 h period before administering. The results obtained regarding MAP (maximal MAP decrease observed over 6 consecutive hours) are summarised in FIG. 9 (data are presented as mean±standard error of the mean). In summary, a dose of 10 mg/kg ACT-132577 decreased MAP by 19±4 mm Hg in Dahl-S rats. In contrast to MAP, HR was not affected.

Example B: Acute Effects of ACT-132577 in Deoxycorticosterone Acetate Salt Rats

The acute effects of ACT-132577 on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) were evaluated by means of telemetry in conscious, male hypertensive deoxycorticosterone acetate salt rats (hereafter “DOCA-salt rats”—see details about this model in Gavras et al., Circ. Res. (1975), 36, 300-309).

In the DOCA-salt rats, hypertension is induced by the combination of unilateral nephrectomy, implantation of pellets of the mineralocorticoid analog DOCA, and provision of 1% sodium chloride in drinking water. Groups of 6-11 DOCA-salt rats were used for the vehicle (7.5% gelatin aquous solution) and each dose of ACT-132577 tested (0.3, 1, 3, 10, 30, 100, and 300 mg/kg). Effects of ACT-132577 on HR and MAP were calculated for individual animals relative to the 24 h period before administering. The results obtained regarding MAP (maximal MAP decrease observed over 6 consecutive hours) are summarised in FIG. 10 (data are presented as mean±standard error of the mean). In summary, a dose of 10 mg/kg ACT-132577 decreased MAP by 29±6 mm Hg in DOCA-salt rats. In contrast to MAP, HR was not affected.

Example C: Acute Effects of ACT-132577 in Spontaneaously Hypertensive Rats

The acute effects of ACT-132577 on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) were evaluated by means of telemetry in conscious, male spontaneaously hypertensive rats (hereafter “SHRs”—see details about this model in Atanur et al., Genome Res. (2010), 20, 791-803).

Groups of 4-6 SHRs were used for the vehicle (7.5% gelatin aquous solution) and each dose of ACT-132577 tested (1, 3, 10, 30, 100, and 300 mg/kg). Effects of ACT-132577 on HR and MAP were calculated for individual animals relative to the 24 h period before administering. The results obtained regarding MAP (maximal MAP decrease observed over 6 consecutive hours) are summarised in FIG. 11 (data are presented as mean±standard error of the mean). In summary, a dose of 100 mg/kg ACT-132577 decreased MAP by 18±4 mm Hg in SHRs. In contrast to MAP, HR was not affected.

Example D: Acute Effects of ACT-132577, Alone or in Combination with Valsartan, in Spontaneaously Hypertensive Rats

The acute effects of ACT-132577 administered orally at a single dose of 100 mg/kg on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”), with ACT-132577 being used either alone or in combination with valsartan administered orally at a single dose of 10 mg/kg, were evaluated by means of telemetry in conscious, male spontaneaously hypertensive rats (hereafter “SHRs”—see details about this model in Atanur et al., Genome Res. (2010), 20, 791-803).

6 SHRs per treatment group were used for this test. The results obtained regarding MAP are summarised in FIG. 12 wherein each data point is presented as a 6-hour mean (NB: the expected additive effect of the combination of the two drugs, referred to as “Predicted additive effect”, was calculated by adding the decreases in blood pressure values obtained after administration of each compound separately); the vehicle (7.5% gelatin aquous solution) treatment had no effect on MAP or HR and the results obtained are therefore not represented in the figure. In brief, co-administration of ACT-132577 and valsartan decreased MAP beyond the predicted (calculated) values, demonstrating synergism between the two molecules. In contrast to MAP, HR was not affected in any of the treatment groups.

Example E: Acute Effects of ACT-132577, Alone or in Combination with Valsartan, in Deoxycorticosterone Acetate Salt Rats

The acute effects of ACT-132577 administered orally at a single dose of 10 mg/kg on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”), with ACT-132577 being used either alone or in combination with valsartan administered orally at a single dose of 30 mg/kg, were evaluated by means of telemetry in conscious, male hypertensive deoxycorticosterone acetate salt rats (hereafter “DOCA-salt rats”—see details about this model in Gavras et al., Circ. Res. (1975), 36, 300-309).

In the DOCA-salt rats, hypertension is induced by the combination of unilateral nephrectomy, implantation of pellets of the mineralocorticoid analog DOCA, and provision of 1% sodium chloride in drinking water. 7-8 DOCA-salt rats per treatment group were used for this test. The results obtained regarding MAP are summarised in FIG. 13 wherein each data point is presented as a 6-hour mean (NB: the expected additive effect of the combination of the two drugs, referred to as “Predicted additive effect”, was calculated by adding the decreases in blood pressure values obtained after administration of each compound separately); the vehicle (4% gelatin aquous solution) treatment had no effect on MAP or HR and the results obtained are therefore not represented in the figure. In brief, co-administration of ACT-132577 and valsartan decreased MAP beyond the predicted (calculated) values, demonstrating synergism between the two molecules. In contrast to MAP, HR was not affected in any of the treatment groups.

Example F: Acute Effects of ACT-132577, Alone or in Combination with Enalapril, in Spontaneaously Hypertensive Rats

The acute effects of ACT-132577 administered orally at a single dose of 100 mg/kg on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”), with ACT-132577 being used either alone or in combination with enalapril administered orally at a single dose of 3 mg/kg, were evaluated by means of telemetry in conscious, male spontaneaously hypertensive rats (hereafter “SHRs”—see details about this model in Atanur et al., Genome Res. (2010), 20, 791-803).

7 SHRs per treatment group were used for this test. The results obtained regarding MAP are summarised in FIG. 14 wherein each data point is presented as a 6-hour mean (NB: the expected additive effect of the combination of the two drugs, referred to as “Predicted additive effect”, was calculated by adding the decreases in blood pressure values obtained after administration of each compound separately); the vehicle (4% gelatin aquous solution) treatment had no effect on MAP or HR and the results obtained are therefore not represented in the figure. In brief, co-administration of ACT-132577 and enalapril decreased MAP beyond the predicted (calculated) values, demonstrating synergism between the two molecules. In contrast to MAP, HR was not affected in any of the treatment groups.

Example G: Acute Effects of ACT-132577, Alone or in Combination with Amlodipine, in Deoxycorticosterone Acetate Salt Rats

The acute effects of ACT-132577 administered orally at a single dose of 10 mg/kg on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”), with ACT-132577 being used either alone or in combination with amlodipine administered orally at a single dose of 1 mg/kg, were evaluated by means of telemetry in conscious, male hypertensive deoxycorticosterone acetate salt rats (hereafter “DOCA-salt rats”—see details about this model in Gavras et al., Circ. Res. (1975), 36, 300-309).

In the DOCA-salt rats, hypertension is induced by the combination of unilateral nephrectomy, implantation of pellets of the mineralocorticoid analog DOCA, and provision of 1% sodium chloride in drinking water. 6-8 DOCA-salt rats per treatment group were used for this test. The results obtained regarding MAP are summarised in FIG. 15 wherein each data point is presented as a 6-hour mean (NB: the expected additive effect of the combination of the two drugs, referred to as “Predicted additive effect”, was calculated by adding the decreases in blood pressure values obtained after administration of each compound separately); the vehicle (4% gelatin aquous solution) treatment had no effect on MAP or HR and the results obtained are therefore not represented in the figure. In brief, co-administration of ACT-132577 and amlodipine decreased MAP beyond the predicted (calculated) values, demonstrating synergism between the two molecules. In contrast to MAP, HR was not affected in any of the treatment groups.

Example H: Chronic Effects of ACT-132577 in Deoxycorticosterone Acetate Salt Rats

The chronic effects of repeated administrations of doses of 1, 10 and 100 mg/kg/day of ACT-132577, in particular mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”), were evaluated in conscious, male hypertensive deoxycorticosterone acetate salt rats (hereafter “DOCA-salt rats”—see details about this model in Gavras et al., Circ. Res. (1975), 36, 300-309). In the DOCA-salt rats, hypertension is induced by the combination of unilateral nephrectomy, implantation of pellets of the mineralocorticoid analog DOCA, and provision of 1% sodium chloride in drinking water. The results of the DOCA-salt rats treated with ACT-132577 were compared to those obtained for Wistar rats or for DOCA-salt rats that received only the vehicle (4% gelatin aquous solution).

a) The results obtained regarding MAP are summarised in FIG. 16 wherein each data point is presented as a 24-hour mean. 6 rats were used for each of the 5 test groups (Wistar control rats (bottom line in FIG. 16), DOCA-salt control rats (top line in FIG. 16) and DOCA-salt rats receiving repeated administrations of doses of 1, 10 and 100 mg/kg/day of ACT-132577 (second to third line from top, respectively, in FIG. 16)). In brief, oral administration of ACT-132577 for 4 weeks dose-dependently attenuated the DOCA-salt-induced increase in MAP without changing HR. b) The results obtained regarding renal vascular resistance are summarised in FIG. 17 wherein:

-   -   DOCA Ø 2 w represents DOCA-salt rats sacrified just before         initiation of treatment with ACT-132577; and     -   the “*” symbol in represents a statistical significance factor         p<0.05 when using a one way ANOVA followed by a Newmal-Keuls         multiple comparisons post-hoc test.

In summary, based on these tests, chronic oral administration of ACT-132577 to DOCA-salt rats dose-dependently increased renal blood flow and decreased renal vascular resistance. ACT-132577 also tended to decrease left ventricular hypertrophy, as suggested by the dose-dependent decrease in plasma concentrations of N-terminal pro-brain natriuretic peptide (NTproBNP).

Example I: Effects of ACT-132577, Alone or in Combination with an ACE Inhibitor or an ARB, in Animal Models of Diabetes

The effects of ACT-132577 can be assessed in diabetic rodent models (in this regard, see the models described in the following references: Sen et al, Life Sci. (2012), 91(13-14), 658-668; Janiak et al., Eur. J. Pharmacol. (2006), 534, 271-279; and Iglarz et al, J. Pharmacol. Exp. Ther. (2008), 327(3), 736-745). In particular, the effect of ACT-132577, alone or in combination, on glucose tolerance, insulinemia and end organ damage can be investigated. End organ damage includes: vascular function, renal function (e.g. proteinuria), cardiac function and remodelling and any other target organ affected by diabetes (e.g. the eye).

Example J: Evaluation of the Effect of ACT-132577 on Fluid Retention

A decrease in haematocrit (Hct) or haemoglobin occurs secondary to an increase in plasma volume and can be used as a marker of fluid retention. A single oral dose of aprocitentan (1-30 mg/kg) or vehicle (gelatin) was administered by gavage to male Wistar rats. Twenty-four hours after administration, sublingual blood was sampled under isoflurane-induced anesthesia. Haematocrit was measured using a hematology analyser. ACT-132577 did not impact on haematocrit (Hct) suggesting low liability on fluid retention (FIG. 18).

Comparison Example 1: Acute Effects of Spironolactone Used in Combination with Valsartan in Spontaneaously Hypertensive Rats

The acute effects of spironolactone (300 mg/kg) on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) in combination with valsartan, each administered orally as single doses, were also evaluated by means of telemetry in conscious, male spontaneaously hypertensive rats (hereafter “SHRs”—see details about this model in Atanur et al., Genome Res. (2010), 20, 791-803) using a protocol analog to that described in Example D.

Unlike for ACT-132577, no synergistic effect was seen on MAP reduction for the combination of spironolactone treatment with valsartan treatment.

Comparison Example 2: Acute Effects of Spironolactone Used in Combination with Valsartan in Deoxycorticosterone Acetate Salt Rats

The acute effects of spironolactone (300 mg/kg) on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) in combination with valsartan, each administered orally as single doses, were also evaluated by means of telemetry in conscious, male hypertensive deoxycorticosterone acetate salt rats (hereafter “DOCA-salt rats”—see details about this model in Gavras et al., Circ. Res. (1975), 36, 300-309) using a protocol analog to that described in Example E.

Unlike for ACT-132577, no synergistic effect was seen on MAP reduction for the combination of spironolactone treatment with valsartan treatment.

Comparison Example 3: Acute Effects of Spironolactone Used in Combination with Enalapril in Spontaneaously Hypertensive Rats

The acute effects of spironolactone (300 mg/kg) on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) in combination with valsartan, each administered orally as single doses, were also evaluated by means of telemetry in conscious, male spontaneaously hypertensive rats (hereafter “SHRs”—see details about this model in Atanur et al., Genome Res. (2010), 20, 791-803) using a protocol analog to that described in Example F.

Unlike for ACT-132577, no synergistic effect was seen on MAP reduction for the combination of spironolactone treatment with enalapril treatment.

Example K: Acute Effects of EXFORGE HCT® Alone, and EXFORGE HCT® in Combination with ACT-132577 or Spironolactone, in Spontaneaously Hypertensive Rats

The acute effects of Exforge HCT® (i.e. a fixed dose combination of valsartan/amlodipine/hydrochlorothiazide; dosage adapted for 1.6 mg/kg/0.1 mg/kg/0.25 mg/kg for valsartan/amlodipine/hydrochlorothiazide, respectively) on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) in combination with ACT-132577 or spironolactone were also evaluated by means of telemetry in conscious, male spontaneaously hypertensive rats (hereafter “SHRs”-see details about this model in Atanur et al., Genome Res. (2010), 20, 791-803).

9 SHRs per treatment group were used for this test. To match the maximal effect on blood pressure of co-administereds drug in this model, aprocitentan 100 mg/kg was administrated orally on the 3^(rd) day following 3-day oral administration of Exforge HCT® mg/kg and spironolactone 300 mg/kg was co-administered orally with Exforge HCT® on the 1^(st) day followed by 2 days of Exforge HCT® administration. The results obtained regarding MAP are summarised in FIGS. 19 and 20 wherein each data point is presented as a 6-hour mean.

When added on top of Exforge HCT®, aprocitentan or spironolactone further reduced blood pressure. However, aprocitentan induced a greater blood pressure reduction than spironolactone. In contrast to MAP, HR was not affected in any of the treatment groups.

Example L: Acute Effects of EXFORGE HCT® Alone, and EXFORGE HCT® in Combination with ACT-132577 or Spironolactone, in Deoxycorticosterone Acetate Salt Rats

The acute effects of Exforge HCT® (dosage adapted for 3.2 mg/kg/0.2 mg/kg/0.5 mg/kg for valsartan/amlodipine/hydrochlorothiazide, respectively) on blood pressure, in particular on mean arterial blood pressure (hereafter “MAP”), and heart rate (hereafter “HR”) in combination with ACT-132577 (10 mg/kg) or spironolactone (300 mg/kg), each administered orally as single doses, were also evaluated by means of telemetry in conscious, male hypertensive deoxycorticosterone acetate salt rats (hereafter “DOCA-salt rats”-see details about this model in Gavras et al., Circ. Res. (1975), 36, 300-309).

In the DOCA-salt rats, hypertension is induced by the combination of unilateral nephrectomy, implantation of pellets of the mineralocorticoid analog DOCA, and provision of 1% sodium chloride in drinking water. 7-9 DOCA-salt rats per treatment group were used for this test. The results obtained regarding MAP are summarised in FIGS. 21 and 22 wherein each data point is presented as a 6-hour mean.

When added on top of Exforge HCT®, aprocitentan 10 mg/kg or spironolactone 300 mg/kg further reduced blood pressure. However, aprocitentan induced a greater blood pressure reduction than spironolactone. In contrast to MAP, HR was not affected in any of the treatment groups. 

1-16. (canceled)
 17. A pharmaceutical composition containing, as active principles, aprocitentan, or a pharmaceutically acceptable salt thereof, in combination with: an angiotensin converting enzyme inhibitor, or a pharmaceutically acceptable salt thereof; as well as at least one pharmaceutically acceptable excipient.
 18. The pharmaceutical composition according to claim 17, wherein said angiotensin converting enzyme inhibitor is enalapril, or a pharmaceutically acceptable salt thereof.
 19. The pharmaceutical composition according to claim 17, said composition comprising aprocitentan in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 17.8°, 20.0°, and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.
 20. A pharmaceutical composition according to claim 17, said composition comprising aprocitentan in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 17.8°, 18.6°, 20.0°, 23.2° and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.
 21. The pharmaceutical composition according to claim 17, said composition comprising aprocitentan in crystalline Form A which essentially shows the X-ray powder diffraction pattern as depicted in FIG. 1, wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.
 22. A method for the treatment of hypertension; heart failure; diastolic dysfunction; chronic kidney disease (CKD); or for the reduction of the risk of developing a major cardiovascular event in patients who have diabetes that is accompanied by at least one other cardiovascular risk factor comprising hypertension; comprising the administration of a pharmaceutically effective amount of aprocitentan, or of a pharmaceutically acceptable salt thereof, to a subject in need thereof, wherein aprocitentan is administered in combination with a pharmaceutically effective amount of an angiotensin converting enzyme inhibitor or a pharmaceutically acceptable salt thereof.
 23. The method according to claim 22, wherein said angiotensin converting enzyme inhibitor is enalapril, or a pharmaceutically acceptable salt thereof.
 24. The method according to claim 22, wherein said method is for the treatment of hypertension.
 25. The method according to claim 23, wherein said method is for the treatment of hypertension.
 26. A method for the treatment of hypertension, heart failure, or chronic kidney disease (CKD); comprising administering a pharmaceutically effective amount of aprocitentan, or of a pharmaceutically acceptable salt thereof, to a subject in need thereof, wherein aprocitentan is administered in combination with a pharmaceutically effective amount of an angiotensin converting enzyme inhibitor or a pharmaceutically acceptable salt thereof.
 27. The method according to claim 26, wherein said angiotensin converting enzyme inhibitor is enalapril, or a pharmaceutically acceptable salt thereof.
 28. The method according to claim 22, wherein the aprocitentan is in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 17.8°, 18.6°, 20.0°, 23.2° and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.
 29. The method according to claim 24, wherein aprocitentan is administered in a pharmaceutical unit dosage form suitable for the oral administration of 10 to 50 mg per day of aprocitentan.
 30. The method according to claim 25, wherein aprocitentan is administered in a pharmaceutical unit dosage form suitable for the oral administration of 10 to 50 mg per day of aprocitentan.
 31. The method according to claim 26, wherein said method is for the treatment of chronic kidney disease (CKD).
 32. The method according to claim 31, wherein said method is for the treatment of CKD of stages 1 to 4 caused by or associated with essential hypertension.
 33. The method according to claim 27, wherein said method is for the treatment of chronic kidney disease (CKD).
 34. The method according to claim 33, wherein said method is for the treatment of CKD of stages 1 to 4 caused by or associated with essential hypertension.
 35. The method according to claim 31, wherein the aprocitentan is in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 17.8°, 18.6°, 20.0°, 23.2° and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.
 36. The method according to claim 33, wherein the aprocitentan is in crystalline Form A characterized by the presence of peaks in the X-ray powder diffraction diagram at the following angles of refraction 2θ: 17.8°, 18.6°, 20.0°, 23.2° and 23.5°; wherein said X-ray powder diffraction diagram is obtained by using combined Cu Kα1 and Kα2 radiation, without Kα2 stripping; and the accuracy of the 2θ values is in the range of 2θ+/−0.2°.
 37. The method according to claim 24, wherein said hypertension is resistant hypertension.
 38. The method according to claim 25, wherein said hypertension is resistant hypertension.
 39. The method according to claim 22, wherein said method is for the treatment of chronic heart failure.
 40. The method according to claim 37, wherein aprocitentan is administered in a pharmaceutical unit dosage form suitable for the oral administration of 10 to 50 mg per day of aprocitentan.
 41. The method according to claim 38, wherein aprocitentan is administered in a pharmaceutical unit dosage form suitable for the oral administration of 10 to 50 mg per day of aprocitentan. 